Force-pump.



W. J. WILLIAMS & J. C. BOWMAN.

FORCE PUMP.

PPPPPPPPPPPPPPPPPPPPPPPPPPP 1,669,750, Patented Aug.12,1913.

WKWJZZL Dyr a (i UNITED STATES PATENT @FFIQE.

WILLIAM J. WILLIAMS AND JAMES C. BOWMAII, OF CHICAGO, ILLINOISFORCE-PUMP.

Application filed July 19, 1909. Serial No. 508,333.

- useful Improvements in Force-Pumps, of

which the following is a full, clear, and exact description.

The invention relates to force pumps and more particularly to means forconnecting a cup-shaped plunger of elastic ma-.

terial to an operating handler It is now common practice to permanentlysecure the handle and plunger together by cement or other means andresultantly, if in the operation of the device, the parts should becomedisconnected, it is difficult to properly connect them.

The invention designs to provide improved means for detachablyconnecting the handle and the elastic plunger, as well as means which issimple in construction and may be produced at a low cost.

.The invention consists in the several novel features hereinafter setforth and more particularly defined by claim at the conclusion hereof.

In the drawings: Figure 1 is a perspective of a pump embodying theinvention. Fig. 2 is a section on a larger scale, the handle being shownin elevation and a portion thereof broken away. Fig. 3 is adetailsection of the plunger.

The pump comprises a plunger 9, having its lower end 10 cup-shaped asusual in the art. The plunger is formed Wholly of elastic material, suchas rubber, and has a hollow integral nipple 11, in which a socket 12 isformed to receive the lower end of a handle 13, which is usually formedof wood. The lower end of the handle has a screwthread 14 cut thereonand at the lower end of the socket 12 a corresponding femalescrew-thread 15 is formed in the elastic material surrounding thesocket. This Specification of Letters Patent. I

Patented Aug. 12,1913.

screw-thread is rather coarse, so that it will not readily break awaywhen subjected to strains. The nipple 11 is thickened adjacent thethread 15 and extends upwardly above the screw-thread to provide anelongated bearing which prevents the thread from being subjected tosevere lateral strains if the handle is operated laterally more'or less.The lower end of handle 13 abuts against the bottom 16 and when thehandle has been inserted in the socket with the screwthread thereonfitting into the female thread 15, the handle and plunger will besecurely connected together. Resultantly, a detachable connection isprovided which makes it possible to disconnect the plunger from thehandle when desired, and if the plunger becomes worn, as it sometimesdoes in practice, a new one may be readily substituted.

Furthermore, by avoiding theuse of cement or the like, the liquid inwhich the plunger is submerged in use will not effect the connection,the elastic nipple permitting the handle to expand from the action ofthe liquid.

Having thus described the'invention, what we claim as new and desire tosecure by Letters Patent, is:

A force pump, comprising a handle having a screw thread at one end, acup-shaped plunger formed of elastic material, and an integral nipple onsaid plunger having a screw thread formed in the lower portion of thesocket therein to detachably connect the threaded end of the handlethereto, said nipple being extended above said screw threaded portion adistance sufiicient to prevent said handle from being pried out of saidnipple during use.

WILLIAM J. WILLIAMS. JAMES C. BOWMAh

